Thursday November 20 2014
Global sales of ADHD drugs are in the billions of pounds
"The global surge in ADHD [attention deficit hyperactivity disorder] diagnosis has more to do with marketing than medicine, according to experts," the Mail Online reports.
But these experts are sociologists, not clinicians, and they present no new peer-reviewed clinical evidence.
That said, they do highlight some interesting interconnected trends about ADHD that are worth attention.
The principal concern of the authors is that ADHD is being medicalised – that is, for a variety of reasons, children who may be simply "naughty" and high spirited are being misdiagnosed with ADHD, and are wrongly being treated with powerful medications such as methylphenidate, better known as Ritalin.
This study concludes that the "global expansion" of ADHD and its subsequent medicalisation has been driven by five major causes:
- drug industry lobbying
- the influence of US-based psychiatry
- the adoption of looser criteria for diagnosis
- the influence of ADHD patient advocacy groups
- the growth of information on the internet
This is a well-researched and interesting article which reflects current concerns about the medicalisation of symptoms that might be viewed as part of the human condition, rather than a disorder that needs drug treatment.
However, this is an opinion piece and is not the last word on this controversial subject.
If you are worried about a child or other relative's behaviour, it is important to see a health professional such as a GP.
Many children go through phases where they are restless or inattentive. This is often completely normal and does not necessarily mean they have ADHD.
Where did the story come from?
The study was carried out by researchers from Brandeis University in the US. There is no information about external funding.
It was published in the peer-reviewed journal Social Science and Medicine.
The Mail Online's coverage was reasonably accurate, but it used the old journalistic cliché "experts say", implying there is a single expert opinion on a subject.
This is very rarely the case, especially when you are dealing with a subject as controversial as ADHD.
What kind of research was this?
This was a narrative review that looked at the evidence for an increase in ADHD across the globe. The authors say how in the US, ADHD has been medicalised for 50 years, but this approach is now being applied internationally.
They document the growth of ADHD diagnosis and treatment in the UK, Germany, France, Italy and Brazil, and look at the possible causes of this expansion.
This article was a narrative review, which means it is subject to selection bias, and is not a systematic review, which looks at all of the available evidence on a topic and uses this information to draw conclusions.
This potential selection bias means the authors may have selected articles to fit their theory.
ADHD is defined as a group of behavioural symptoms that include inattentiveness, hyperactivity and impulsiveness.
There is a school of thought that the diagnosis of ADHD can be prone to medicalisation, where normal human behaviour is defined and treated as illness.
But others argue this condition is being picked up more frequently as a result of better education and recognition of symptoms.
What does the study say?
The study looked at evidence for the "globalisation" of ADHD and the increase in the use of ADHD medication, such as methylphenidate (Ritalin).
In particular, it examined the prevalence and treatment of ADHD in five countries – the UK, Germany, France, Italy and Brazil.
In the UK, the authors state ADHD is now the most prevalent behavioural disorder, with an estimated 3-9% of children and adolescents having the condition.
Drug treatment for ADHD has also been on the rise here, with one recent report suggesting methylphenidate (Ritalin) prescriptions rose by 11% in GP practices, and by 24% in private practice from 2011-12.
The authors partly ascribe this increase to changes in diagnostic criteria used in the UK. In the past, the UK adopted criteria from the World Health Organization (WHO) for a condition then called hyperkinetic disorder.
But there is now a greater use of US criteria globally, which uses different terminology and provides a lower threshold for diagnosis.
The article goes on to look at what it says are the major trends behind this rise in diagnosis and treatment in some countries.
Influence of drug companies
In the past, drugs for ADHD were heavily marketed in the US, but as this market has become saturated, the industry has expanded into international markets and promoted ADHD drug treatment around the world – first in western Europe, but also in other countries such as Brazil, Mexico and Japan.
Influence of US psychiatry
There has especially been a move towards "biological" psychiatry, where mental and behavioural disorders are treated with drugs rather than psychotherapy. More psychiatrists across the globe are now trained in the US and import US practices into their countries of origin.
Recent growth in the adoption of different criteria for ADHD
The authors say until the 1990s, many countries used the International Classification of Mental and Behavioral Disorders (ICD), published by WHO, which has strict criteria for ADHD. But since then, other countries have adopted the Diagnostic and Statistical Manual of Mental Disorders (DSM), published by the American Psychiatric Association, which has a lower threshold for diagnosis of ADHD.
Wide availability of information on the internet
The authors say there is "endless information on various sites about ADHD from numerous sources, including pharmaceutical websites". In particular, they point out the availability of ADHD checklists based on US screening devices. These allow internet users to "measure" certain behaviours that could lead to a possible ADHD diagnosis, prompting more consumers to ask for drug treatment.
Influence of ADHD advocacy groups
These groups often work closely with drug companies and promote drug treatments. The authors point out how in some countries, such as France and Italy, ADHD rates are lower. This is thought to be a result of a cultural tradition of using psychoanalytic rather than drug-based approaches for behavioural problems, and restrictions on the use of ADHD medication.
How did the researchers interpret the results?
The authors predict the medicalisation of ADHD will expand further to cover more countries.
This could also happen to other conditions, and divert attention away from "important social and structural approaches" to global health, they argue.
This is an interesting paper that shows there has been an increase in ADHD diagnosis and treatment in several countries, including the UK, and examines the reasons why this may have occurred. The possible "medicalisation" of ADHD has been an issue of concern and debate for some time.
As the authors note, the paper has some limitations. They selected countries where there is available published literature on ADHD, so their conclusions may not be generalisable to other countries.
Further research is needed to explore the approaches to ADHD in parts of the world that have received less attention, such as Asia, eastern Europe, the Middle East and Africa.
The authors used research on ADHD to support their opinion about the medicalisation and globalisation of this disorder. Others might disagree, arguing that more awareness has led to an increase in diagnosis, and drug treatment can be helpful in many cases.
If you are worried about a child's or other relative's behaviour, it's important to see a GP or other healthcare professional. Many children go through phases where they are restless or inattentive. This is often completely normal and does not necessarily mean they have ADHD.
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.